Intracytoplasmic sperm injection

Microinjection revolutionised the treatment of infertility due to male causes. ICSI consists of introducing a sperm in each mature egg to allow its fertilisation. It is used in cases of low quality or quantity of sperm (few sperm, with low motility and/or morphology changes).

ICSI is also used in couples whose prior IVF treatments had failed fertilisation.

The treatment protocol is similar to IVF concerning the ovarian stimulation, egg collection and posterior embryonic division.

Even in situations with no sperm in the ejaculate, it might be possible to obtain them through a testicular biopsy (TESA), which can then be used in ICSI to fertilise the eggs.